Straightening machine



06L 1967 G. A. E. COUTURE 3,347,073

STRAIGHTENING MACHINE Filed April 28, 1964 3 Sheets-Sheet l ATTORNEYS 9 1967 G. A. E. COUTURE ,34

STRAIGHTENING MACHINE Filed April 28, 1964 3 Sheets-Sheet 2 9%? o /22 FIGZ FIGB FIG4

INVENTOR.

JWWW ATTORNEYS 1957 G. A. E. COUTURE 7 3,

STRAIGHTENING MACHINE Filed Apl 28, 1964 3 Sheets-Sheet 5 "'n I I FIGG FIGBG L., L; I O 1/6 CYLINDAR 98 LI "rm 1 3 i1 IOO I02 I I l l 96 /94 1 r T CONTACT PLATE FEED I08 DRIVE CLUTCH P RACK I46 1 T DRIVE INVENTOR.

CLUTC? 31W Q8. Caufim, FIG? 82 BY ATTORNEYS United States. Patent 3,347,073 STRAIGHTENING MACHINE George A. E. Couture, 1180 Murray Ave., Quebec 6, Quebec, Canada Filed Apr. 28, 1964, Ser. No. 363,144 10 Claims. (Cl. 72-15) This invention relates to a machine for bending articles into the desired shape and more particularly comprises a new and improved machine for automatically straightening tempered items such as blades, spring leaves and shafts which become distorted in an irregular fashion when heat treated. At the present time, distortions in those items are corrected manually. Each item is individually inspected and when found to be distorted in any Way, a time consuming hand operation is employed to correct the irregularities found.

One important object of this invention is to obviate the need for manually straightening tempered blades, spring leaves, shafts, etc. during the manufacture and to provide a machine for automatically hammering the items into the desired shape.

Another important object of this invention is to provide an automatic straightening machine that receives items on an individual basis, tests each item for straightness, and automaticlly straightens each item which is distorted.

A more general object of this invention is to increase the rate at which items may be inspected and straightened in the manufacturing facility.

Still another important object of this invention is to provide a machine for automatically hammering the straightening distorted items, which is suitable to be used in a modern manufacturing facility to perform one of the automatic steps in the production line.

To accomplish these and other objects this invention includes among its many features, a frame carrying conveying means which describes a course along which articles to be straightened are directed. A continuously reciprocating hammer is mounted on the frame and is normally disposed in a first position wherein the hammer does not strike the articles moving along the course. The reciprocating hammer is movable to a second position on the frame wherein it can strike the articles. A sensing device is included as part of the assembly and responds to an abnormality in the shape of the article for moving the hammer from the first to the second position.

These and other objects and features of this invention along with its incident advantages will be better understood and appreciated from the following detailed description of one embodiment thereof, selected for purposes of illustration and shown in the accompanying drawing, in which:

FIG. 1 is an elevation view of a straightening machine constructed in accordance with this invention;

FIGS. 2, 3 and 4 are a series of fragmentary side views illustrating the sequence of steps performed by the machine of FIG. 1 to straighten an article directed through it;

FIG. 5 is a perspective view of a portion of the machine shown in FIG. 1;

FIG. 6 is a perspective view, partly in section, of a portion of the assembly shown in FIG. 5;

FIGS. 6a and 6b are detail view of a part of the assembly shown in FIG. 6; and

FIG. 7 is a schematic diagram of the electro-pneumatic control circuit of the straightening machine.

The machine shown in FIG. 1 includes a frame 10 having an inclined table 12 on which most of the machine parts are mounted. The operative mechanism of the device consists basically of three parts; namely, the conveyor system 14, the hammer assembly 16, and the control circuit.

The conveyor system 14 includes two separated pairs 26 and 22 of spaced rollers 24. The separated pairs of rollers describe a course above the table 12 along which articles to be straightened are directed and in which the hammer assembly 16 performs its function to remove any distortions in the articles being handled. The lower roller of each pair is mounted on the frame 10 a fixed distance above the table 12 while the upper rollers of the pairs are spring loaded as suggested in FIGS. 2-4 to bear down upon the articles as each is fed between the pairs of rollers. As viewed in FIG. 1, the articles being handled by the machine are fed between the rollers from the upper end of the table 12 and are conveyed along the course defined by the rollers toward the lower end.

The pairs of rollers 20 and 22 are driven by a chain and sprocket assembly 26 shown in FIG. 1 connected to the output shaft 27 of a gear reducer 28 in turn driven by a motor 30 through belt and pulley assembly 32. An air clutch 34 is secured to the output shaft 36 of the motor 30 for engaging and disengaging the lower pulley 38 with the shaft 36. A diaphragm-type brake 40 is secured to the input shaft 42 of the gear reducer 28 to prevent drifting of and positively stop the rollers 24.

Just beyond the lower pair 22 of rollers is a contact plate 44 which is insulated from the frame 10 and table 12 by an insulating layer 46. The contact plate 44 is positioned to lie in the path of any article fed between the rollers and along the course described by them, which is not straight. This is suggested in FIGS. 2-4. In FIG. 2 and article 50 is shown being conveyed to the right between the rollers 20 and 22, and the article extends above the plate 44. Because the article 50 is straight it does not engage the contact plate 44. In FIG. 3 an article 50a is shown shortly after it has entered between the pairs of rollers 20 and 22, and the leading edge 50b of the article is touching the contact plate 44 because the portion of the article between the rollers is distorted. When the portion of the article 59a between the pairs of rollers is straightened the article will not again contact the plate 44 until the bend at the trailing end lies between the rollers causing the leading tip 50b to drop. It is apparent from an inspection of FIG. 4 that as the article 50a is conveyed to the right as viewed in that figure between the rollers 20 and 22, its leading tip 50b will again dip downwardly and engage the upper surface of the contact plate 44.

The hammer assembly 16 which pounds the articles into shape is supported above the upper surface of the table 12 by a number of columns 52. The hammer assembly includes a hammer 54 disposed above the rollers midway between the pairs 20 and 22. The hammer 54 is disposed normal to the course described by the pairs of rollers and is oriented to strike articles in the course which engage the contact plate 44. As the hammer 54 strikes the articles from above, the lower rollers of the pairs serve as anvils for the hammer assembly.

The hammer 54 effectively has two separate inputs; namely, one input which causes the hammer 54 to continuously reciprocate axially toward and away from articles carried by and disposed between the rollers, and another input which causes the hammer while reciprocating, to move downwardly towards the article in the course described by the pairs of rollers. While the hammer 54 continuously reciprocates, the reciprocal stroke of the hammer does not ordinarily carry the impact end 56 to the surface of the article supported on the rollers, but when the hammer is lowered by its second input, the stroke of the hammer is such that its impact end strikes the article supported on the rollers. Both inputs of the hammer 54 employ motor 58 as the power source, which through V-belt assembly 59, turns a drive shaft 60 that carries an eccentric 62. The eccentric 62 carries a block 64 which is slidable laterally in eccentric box 66 closed within a number of plates 68. The box 66 free to move vertically carries 21 depending collar 70 on its bottom provided with a slot on its inner surface which cooperates with a key 72 on the hammer 54 to prevent the hammer from rotating. The key 72 and the slot limit movement of the hammer 54 relative to the collar 70 and box 62 to an axial direction. The collar 70 at its upper end surrounds an internally threaded gear 74 screwed onto the upper threaded portion 76 of the hammer 54. Thus the gear 74 serves to secure the hammer 54 to the eccentric box 66.

When rotation is imparted to the shaft 60 the eccentric 62 rotates moving the block 64 in a circular path with it. The block 64 is slidable within and movable relative to the box 66 only in a horizontal direction and imparts only vertical reciprocation to the box 66 and the hammer 54 carried by it. The box 66 is constrained to a vertical path by the plates 68 which surround it.

The gear 74 forms part of the second input to the hammer 54 to lower its stroke. The gear 74 which is rotatably mounted within the upper end of the collar 70 is in driving contact with rack 78. The rack extends through the upper portion of the collar 70 and registers with the external teeth of the gear 74. Thus, when the rack moves in one direction and turns the gear 74, the internal threads of that gear act upon the upper threaded portion 76 of the hammer 54 to lower it relative to the box 66, and when the rack moves in the opposite direction the internal threads on the gear 74 take up the upper threaded portions 76 of the hammer 54 and elevate it relative to the box.

The rack 78 is driven by a gear 80 in turn driven through a pneumatic clutch 82 connected to the output of a ratchet or sprag assembly 84. The input arm 86 of the sprag 84 is connected through a ball and socket joint 88 to the crank arm 90 of an eccentric 92 carried on the end of shaft 60. The sprag 84 in response to rotation of the shaft 60 imparts rotation to the gear 80 in the direction of arrow A. When the gear 80 rotates in the direction of arrow A the rack 78 moves in the direction of arrow B, which lowers the hammer 54 in the collar 70. Thus, the stroke of the hammer 54 is lowered with respect to the box 66 when the rack 78 moves in the direction of arrow B. When the rack is returned to its normal position by being moved in the direction of arrow C, the hammer 54 is elevated in the collar and its stroke is accordingly raised above the course i defined by the pairs of rollers 20 and 22 on the table 12.

In FIG. 7 the electro-pneumatic control circuit for the straightening machine is illustrated. The circuit includes a sensing electrical circuit 94 and a pneumatic clutch, brake and rack control 96. The sensing circuit 94 is shown connected to a 110 volt line L L through a step down trans-. former 98. One side of the output coil 100 of the transformer is shown grounded at 102, and the other side of the transformer is connected to coil 104 of relay 106, whose other side is connected to the contact plate 44. This end of the sensing circuit 94 is adapted to be connected to ground either by engagement of the contact plate 44 by the article being straightened by the machine as suggested by article 50a in FIG. 7, or by closing of the switch 108. The switch 108 forms part of contact breaker 110 that is more fully described in connection with FIGS. 6, 6a and 6b.

The pneumatic system 96 is connected through solenoid valve 112 to air pressure source 114 utilized to operate the clutches 34 and 82, the brake 40 and the air cylinder 116 which serves to move the rack 78 in the direction of arrow C shown in FIG. 5. That is, the air cylinder 116 serves to return the rack 78 to its normal position after it has been displaced from that position by operating the gear 80.

The solenoid valve 112 is designed to alternately connect the air pressure source 114 to the conduits 118 and 4 120. The conduit 118 is connected to the clutch 34 and the cylinder 116 while the conduit 120 is connected to the clutch 82 and brake 40. Thus in one condition the sole noid 112 maintains the clutch .34 engaged and the rack 78 withdrawn, and in a second condition the solenoid maintains the clutch 82 engaged and the brake 40 on. The solenoid 112 is energized from the 110 volt source through the switch 122 of relay 106. Because the clutches 34 and 82 are alternately engaged (under no normal operation of the machine are they ever engaged simultaneously), it is seen that when the rollers 24 of the pairs 20 and 22 are driven to convey the article being straightened through the machine, the clutch 82 is engaged so the hammer stroke is lowered to strike the article, the rollers 24 do not rotate to transport the work through the machine and the brake positively locks them in a fired position. Only after the hammer corrects any abnormality in the article so that it no longer touches the contact, plate 44 is the hammer again elevated and the article conveyed through the norv mal course of the machine.

As indicated above the circuit for the relay coil 104 I may be energized either by connecting the contact plate 44- to ground through the article 50a being handled or through the contact breaker 110 which includes switch 108. The contact breaker 110 is provided to maintain the circuit of coil 104 energized duringthose periods when instanta ncous vibrationof the article under the blows of a hammer temporarily open the contact between the article and the contact plate 44. Thus, the contact breaker 110 is designed to maintain the coil 104 energizedduring the portion of each cycle when the hammer strikes the article, and for a short period thereafter to permit the vibrations to dissipate.

The contact breaker 110 is shown in detail in FIGS. 6, 6a and 6b. In FIG. 6 the hub of extension shaft 132 is shown bolted to the pulley 59a of the V-belt drive 59 so that the shaft 132 rotates with the pulley and the drive shaft 60 of the hammer. A bearing assembly 134 is mounted on the inner end of the extension shaft 132 and supports a timing ring 136 which is rotatable with. respect to the extension shaft 132 because of the bearing support. The timing ring 136 is releasably locked to a sleeve 138 by means of set screw 140. The sleeve 138 is rigidly secured to the frame 10 of the machine by bracket 142. Thus the sleeve 138 does not rotate with the extension shaft 132, but rather remains fixed, and the. shaft 132 rotates within it. The timing ring 136 carries the cam follower 144 with it, which in turn rides on the outer surface of cam 146 keyed to the extensionshaft 132. The cam 146 secured to the shaft and rotatably locked to it by key 148 has a dwell 150 provided on its surface which gradually increases in angular span from end 152 to end 154. The cam 146 is urged by means of spring 156 outwardly on the shaft extension 132, and the knurled nut 158 threaded on the shaft 132 is designed to move the cam 146 against the bias of the spring so that the effective angular span of the dwell maybe varied.

The contact breaker assembly shown in FIG. 6 includes two adjustments. First, the span of the dwell may be varied by moving the cam 146 into or out of the timing ring 136 so that the follower 144 rests upon a portion of the cam having a smaller or greater dwell as desired. Second,

the period in each cycle during which the dwell is engaged by the follower 144 may be varied by loosening the set screw and moving the timing ring 136 relative to the fixed sleeve 138. Thus, both the duration of the dwell and its period within each cycle may be adjusted. The particustraightened if they are to be suitable for the use intended. The blades are fed to the machine at the higher end of table 12 and may be directed either manually or automatically to the first pair 20 of rollers. As no contact is made between the blade as it is introduced and the contact plate 44 the circuit for the coil 104 of relay 106 is open and the solenoid valve 112 is deenergized. As a result the clutch 34 is engaged and the cylinder 116 retains the rack 78 in its withdrawn position maintaining the hammer stroke above the level of the blade. The motor 58 through the V-belt drive 59 rotates the shaft 60 which causes the hammer 54 to continuously reciprocate. The clutch 82 is disengaged and the brake 40 is released so that the hammer stroke is not lowered, and the motor 30 is free to'drive the rollers 24 through the chain and sprocket assembly. If the blade passing through the machine is straight it will not engage the contact plate 44 and consequently the blade will continue through the course described by the pairs of rollers. A microswitch 160 resting on the upper roller 24 of the first pair 20 will sense any abnormal deflection of the roller due to excessive blade thickness or other imperfection in the blade being conveyed by the rollers and can be connected through a circuit (not shown) to shut down the machine.

In the embodiment of the invention illustrated in the drawing, blades may be visually inspected before being introduced between the rollers, and if any curvature is evident the concave side of the blade is faced downwardly toward the table 12. Any blades having a double curvature (those which are S-shaped) should be run through the machine twice, inverting the blade between runs. If the blade being conveyed through the machine by the roller pairs 20 and 22 is downwardly concaved, its leading edge will engage the contact plate 44 in the manner shown in FIG. 3, and the sensing circuit 94 will be grounded by the blade through the frame and the relay coil 104 will become energized. Consequently the relay switch 122 will close, the solenoid 112 will be energized and the air source 114 will be disconnected from the duct 118 and will be connected to the duct 120. Consequently the clutch 34 will cause the ratchet or sprag assembly 84 to turn the cylinder 116, the brake 40 will be applied to stop further rotation of the rollers 24 resulting in the immediate stoppage of the blade in its travel along the course, and the clutch 82 will be engaged. Engagement of the clutch 82 will cause the ratchet or sprag assembly 84 to turn the gear 80 through a selected number of degrees during each revolution of the shaft, and the hammer stroke 54 will move downwardly step by step in the direction of the blade captured between the rollers. After one or a few revolutions of the shaft 60, the hammer 54 will strike the blade supported on the lower roller of each pair that serve as anvils. As the hammer 54 strikes the blade being straightened, the cam 146 of the contact breaker will engage the blade 144 to provide an alternate energizing circuit for the coil 104 of the relay 106, and this alternate circuit will continue to serve as a substitute for the circuit through the contact plate for a short duration afer each blow is struck. Consequently the circuit for the coil 104 is not interrupted and the blade will not be advanced by the rollers before complete correction is made. It may be noted that the relay is damped so that the momentary closing of the circuit by the contact breaker is not sufiicient to initially energize the relay, but once energized by the contact plate connection to ground, the contact breaker can maintain the relay energized.

Because the stroke of the hammer 54 is lowered with each revolution of the shaft 60, when the clutch 82 is engaged it will be appreciated that the hammer strikes the blade with increased severity during each revolution of the shaft. The force with which the hammer strikes the work therefore increases continuously until the blade is sufficiently straightened so that its leading end breaks contact with the plate 44. When this occurs the relay is deenergized, the solenoid 122 is deenergized, and once again 6 the compressed air source is connected to duct 116 to withdraw the rack 78. Simultaneously the clutch 82 is disengaged to allow the rack 78 to be withdrawn without stripping the teeth from the gear 80, and the brake 40 is released to allow the rollers to once again turn and convey the blade. Operation of the rollers continues until the leading edge of the blade once again engages the contact plate 44 as will occur when the blade has the curvature suggested in FIG. 4. When contact is made with the plate 44, the hammer 54 is again lowered, the rollers stop, and successively heavier blows are struck until the blade is again lifted from the contact plate.

While the machine described above is capable of correcting only those blades which are placed in it with the convex side facing upwardly and would require two passes of a blade to remove any double curvature, it will be appreciated that in an alternate embodiment of this invention a machine could employ two hammers and two sensing circuits with contact plates on each side of the course described by the rollers. One hammer would be capable of striking upwardly against the bottom of the blade while the other hammer would strike downwardly as in the embodiment illustrated.

The foregoing description will suggest numerous modifications to those skilled in the art. For example, the actuating mechanism for the hammer 54 may be changed as can the electropneumatic control circuit. Therefore, it is not intended that the scope of this invention be limited to the single embodiment illustrated and described. Rather, it is intended that the scope of this invention be determined by the appended claims and their equivalents.

What is claimed is:

1. A straightening machine comprising a frame,

two pairs of spaced rollers on the frame through which articles to be straightened are directed, said rollers describing a course through which straight articles will pass without interruption,

a hammer mounted on the frame for reciprocal movement along a path normal to the course and between the pairs of rollers, said reciprocal movement along the path defining the hammer stroke,

means continuously reciprocating the hammer along the path with the limits of the stroke failing to intersect the course,

drive means for driving the rollers to propel articles along the course,

sensing means responsive to an article leaving the course and connected to the drive means for stopping the rollers to retain the article in a fixed position, said means also being connected to the reciprocating means for moving the reciprocating hammer while it continuously reciprocates so that its stroke intersects the course and strikes the article,

and means operatively connected to the sensing means for returning the reciprocating hammer to a position wherein the hammer stroke fails to intersect the course and it fails to strike the article.

2. A straightening machine comprising a frame,

means on the frame describing a course along which articles to be straightened are directed,

a continuously reciprocating hammer mounted on the frame biased to a first position wherein its reciprocal stroke does not reach the course and movable to a second position while it continues to reciprocate wherein the stroke intersects the course,

and means mounted on the frame and responsive to the presence of an article which extends off the course for moving the hammer from its first to its second position.

3. A straightening machine comprising 7 a frame carrying a hammer support and a work piece conveyor,

said conveyor describing a course established for work pieces of a selected configuration carried by the conveyor,

drive means for continuously reciprocating a hammer mounted on the support through a stroke,

a hammer connected to the drive means and mounted on the support and biased to a position wherein its stroke does not penetrate the course, sensing means mounted on the frame adjacent the conveyor and connected to the hammer support and responsive to a work piece extending out of the course for moving the hammer so thatits stroke penetrates the course with increased depth with each reciprocation, and means connected to the sensing means for moving the hammer support so that the hammer strokes no longer penetrate the course when the sensing means determines that the piece is confined to the course. 4. A straightening machine as described in claim 3 and further characterized by means connected to the conveyor and operatively controlled by the sensing means for stopping the conveying means when the sensing means responds to a work piece extending out of the course. 5. A bending machine as defined in claim 4 further characterized by,

said conveyor including separated pairs of spaced rollers, with the rollers of each pair being spaced a distance substantially equal to the thickness of the work pieces to be handled by the machine, and drive means for turning the rollers to convey work pieces through the machine, said hammer being disposed on the support in a position to strike the work pieces between the separated pairs of rollers. 6. A bending machine as defined in claim 5 further characterized by said sensing means including a contacting plate dis posed adjacent the course established by the separated pairs of rollers and in the path of the work pieces when they stray to one side of the established course. 7. A bending machine comprising a frame carrying a hammer support and a conveyor, a hammer carried by the hammer support, continuously operating drive means for continuously moving the hammer through a reciprocal stroke, moving means connected to the hammer support for moving the stroke closer to the course established by the conveyor for work pieces directed through the machine, said means being biased to a position wherein the stroke does not reach said rib pieces,

energizing means for operating the conveyor,

clutches disposed in the moving means and the energizing means,

sensing circuit including means responsive to the work piece moving from the course established by the conveyor for opening the clutch in the energizing means and closing the clutch in the moving means,

and switching means forming part of the circuit for maintaining the clutch of the energizing means disv engaged and the other clutch engaged as the hammer strikes the work piece.

8. A straightening means comprising a continuously reciprocating hammer,

an anvil for supporting articles to be straightened by the hammer,

sensing means disposed adjacent the anvil and responsive to an irregularity in the shape of an article on the anvil for lowering the hammer as it reciprocates so that it continuously strikes the article until the irreguarity detected is corrected, and biasing means secured to the hammer for yieldably holding the continuously reciprocating hammer so that it does not strike the article. 9. A straightening means as defined in claim 8 further characterized by the sensing means including a circuit having a contact plate disposed adjacent the anvil and adapted to be engaged by an article which is irregularly shaped, said engagement closing the circuit, and means forming part of the sensing means for closing the circuit during momentary interruptions in the engagement of the plate by the article due to vibrations of the article as the hammer strikes it. 10. A straightening machine as defined in claim 3 further characterized by the means connected to the sensing means is driven by the drive means.

References Cited UNITED STATES PATENTS 2,818,798 11/1954 Deykin --257 3,162,232 12/1964 Munschauer et a1. 72441 3,181,322 5/1965 Lehacque 7217 CHARLES W. LANHAM, Primary Examiner.

R. D. GREFE, Examiner. 

1. A STRAIGHTENING MACHINE COMPRISING A FRAME, TWO PAIRS OF SPACED ROLLERS ON THE FRAME THROUGH WHICH ARTICLES TO BE STRAIGHTENED ARE DIRECTED, SAID ROLLERS DESCRIBING A COURSE THROUGH WHICH STRAIGHT ARTICLES WILL PASS WITHOUT INTERRUPTION, A HAMMER MOUNTED ON THE FRAME FOR RECIPROCAL MOVEMENT ALONG A PATH NORMAL TO THE COURSE AND BETWEEN THE PAIRS OF ROLLERS, SAID RECIPROCAL MOVEMENT ALONG THE PATH DEFINING THE HAMMER STROKE, MEANS CONTINUOUSLY RECIPROCATING THE HAMMER ALONG THE PATH WITH THE LIMITS OF THE STROKE FAILING TO INTERSECT THE COURSE, DRIVE MEANS FOR DRIVING THE ROLLERS TO PROPEL ARTICLES ALONG THE COURSE, SENSING MEANS RESPONSIVE TO AN ARTICLE LEAVING THE COURSE AND CONNECTED TO THE DRIVE MEANS FOR STOPPING THE ROLLERS TO RETAIN THE ARTICLE IN A FIXED POSITION, SAID MEANS ALSO BEING CONNECTED TO THE RECIPROCATING MEANS FOR MOVING THE RECIPROCATING HAMMER WHILE IT CONTINUOUSLY RECIPROCATES SO THAT ITS STROKE INTERSECTS THE COURSE AND STRIKES THE ARTICLE, AND MEANS OPERATIVELY CONNECTED TO THE SENSING MEANS FOR RETURNING THE RECIPROCATING HAMMER TO A POSITION WHEREIN THE HAMMER STROKE FAILS TO INTERSECT THE COURSE AND IT FAILS TO STRIKE THE ARTICLE. 